19-4334; Rev. 5; 9/95
Lo w -Co s t , µP S u p e rvis o ry Circ u it s
5–70/MAX813L
_______________Ge n e ra l De s c rip t io n
___________________________Fe a t u re s
♦ µMAX Package: Smallest 8-Pin SO
The MAX705-MAX708/MAX813L microprocessor (µP)
supervisory circuits reduce the complexity and number
of components required to monitor power-supply and
battery functions in µP systems. These devices signifi-
cantly improve system reliability and accuracy com-
pared to separate ICs or discrete components.
♦ Guaranteed RESET Valid at VCC = 1V
♦ Precision Supply-Voltage Monitor
4.65V in MAX705/MAX707/MAX813L
4.40V in MAX706/MAX708
♦ 200ms Reset Pulse Width
The MAX705/MAX706/MAX813L provide four functions:
♦ Debounced TTL/CMOS-Compatible
1) A reset output during power-up, power-down, and
brownout conditions.
Manual-Reset Input
♦ Independent Watchdog Timer—1.6sec Timeout
2) An independent watchdog output that goes low if
the watchdog input has not been toggled within 1.6
seconds.
(MAX705/MAX706)
♦ Active-High Reset Output
(MAX707/MAX708/MAX813L)
3) A 1.25V threshold detector for power-fail warning,
low-battery detection, or for monitoring a power sup-
ply other than +5V.
♦ Voltage Monitor for Power-Fail or Low-Battery
Warning
4) An active-low manual-reset input.
The MAX707/MAX708 are the same as the MAX705/
MAX706, except an active-high reset is substituted for
the watchdog timer. The MAX813L is the same as the
MAX705, except RESET is provided instead of RESET.
______________Ord e rin g In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
8 Plastic DIP
8 SO
MAX705CPA
MAX705CSA
MAX705CUA
MAX705C/D
Two supply-voltage monitor levels are available: The
MAX705/MAX707/MAX813L generate a reset pulse when
the s up p ly volta g e d rop s b e low 4.65V, while the
MAX706/MAX708 generate a reset pulse below 4.40V.
All four parts are available in 8-pin DIP, SO and µMAX
packages.
8 µMAX
Dice*
Ordering Information continued at end of data sheet.
* Dice are specified at T = +25°C.
A
**Contact factory for availability and processing to MIL-STD-883.
_______________________Ap p lic a t io n s
Computers
Controllers
_________________P in Co n fig u ra t io n s
TOP VIEW
MR
Intelligent Instruments
Automotive Systems
Critical µP Power Monitoring
WDO
1
2
3
4
8
7
6
5
V
CC
RESET (RESET)
WDI
MAX705
MAX706
MAX813L
GND
PFI
PFO
__________Typ ic a l Op e ra t in g Circ u it
DIP/SO
UNREGULATED DC
MAX667
+5V DC LINEAR
REGULATOR
MR
RESET
RESET
N.C.
1
2
3
4
8
7
6
5
µP
V
CC
V
MAX707
MAX708
CC
GND
PFI
V
CC
RESET
PFI
RESET
I/O LINE
PFI
PFO
MAX705
MAX706
MAX813L
WDO
PFO
NMI
INTERRUPT
MR
DIP/SO
PUSHBUTTON
SWITCH
( ) ARE FOR MAX813L ONLY.
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
Ca ll t o ll fre e 1 -8 0 0 -9 9 8 -8 8 0 0 fo r fre e s a m p le s o r lit e ra t u re .